Young adults with a certain variant of the dopamine receptor D4 (the DRD4 gene) are more likely to have a history of uncommitted sex, including one-night stands and acts of infidelity, according to a new study. This means that more people with this gene are likely to be cheaters. Previous studies have also linked this gene to increased gambling and alcohol use.

The study's leader Justin Garcia said:

"The motivation seems to stem from a system of pleasure and reward, which is where the release of dopamine comes in. In cases of uncommitted sex, the risks are high, the rewards substantial and the motivation variable - all elements that ensure a dopamine "rush.